I noticed something this last weekend when shooting a couple's 20th-anniversary portraits at Manistee Ranch, a popular park for photo sessions located in Glendale, AZ. Out of about a dozen photographers spread out throughout the park shooting clients including young children, couples, wedding parties, and quinciñeras, only two photographers appeared to be using any form of light modifiers or reflectors, and one may have had an on-camera flash with a bounce card. I was the only one there using off-camera flash w/ a modifier. Are most photographers content with the results using natural light, or are they apprehensive of taking control of the light in their images in a flattering way?
Using the camera's built-in flash (if equipped) or an unmodified speed light on the camera pointed directly at the subject produces harsh light that isn't flattering for your subjects. Moving the light off the camera and diffusing or modifying it to soften, focus, or contain the light not only helps control the intensity, softness, and fall-off of the light but also changes the direction of the light for more flattering results.
Shooting with off-camera flash doesn't have to be expensive or difficult. A $28 Amazon Basics manual flash, some basic RF triggers, a modifier to soften the light (like a shoot-through umbrella or softbox), and something to attach it all to (i.e. a monopod with a 5/8" stud with a softbox adapter or a small light stand) is all it takes. All in, you're probably looking at $100-$150 on the low-end to completely transform the look of your photos. Spending a bit more will allow you to shoot in broad daylight with something high-speed-sync capable (where you can use shutter speeds above 1/200-1/320 sec to darken ambient light). Spending a lot more on battery-operated mono-lights adds more power in some cases, but isn't necessary (or as portable) in most situations.
For someone getting started with off-camera flash wanting to shoot on location, here's a kit I'd suggest (note: some parts are Nikon specific, but there are Canon equivalents):
All in: ~$265 (or <$200 if opting for one flash).
* all prices in USD on Amazon.com as of 16-Sept-2017.
Here's a photo of my assistant (aka my daughter) holding my setup using a carbon-fiber monopod. Shown here is a different flash and trigger setup than mentioned above, but both products are discontinued. Besides, I cannot recommend the Aperlite flash (see link for my Amazon review) and the Neewer triggers are no longer available for sale. The Yongnuo flash units listed above have built-in receivers and don't require external trigger receivers (fewer batteries to charge). I know other photographers that use the Yongnuo combination listed above that easily recommend them.
If you're a Nikon shooter like I am, you may ask if using Nikon's built-in CLS system is a good option with a compatible flash. While it does work well in some settings (I started out with this before moving to RF triggers), the optical system doesn't deliver consistent results outdoors where bright light can blind the receiver on the flash, and it requires line-of-sight from the camera to the flash to trigger reliably. Additionally, some higher-end bodies don't include a built-in pop-up flash to trigger the flashes, and lower-end D-SLR bodies (Nikon D3000-series and D5000-series) don't offer the system at all unless you add an external optical trigger unit costing hundreds more than the setup I mentioned above. At the end of the day, an RF trigger is far more reliable and doesn't require line-of-sight to trigger.
As for how to make this all work, there are many great classes at your local camera store or online (YouTube, Digital Photography School, Fro Knows Photo, Lynda, etc.), both free and paid, that will help you to get over the hump of using flash, understanding how it affects exposure, the relationship of shutter speed to ambient light vs aperture to flash exposure in an image, and more. A quick Google or YouTube search will get you started down a new journey and a new way of looking at photos! I personally paid for a course that was less than $70 online and in a few hours, was eager to try out what I had learned. The key is to practice until you can repeatedly achieve the desired results in your images.
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